Use of DHA fish oil capsules does not decrease postpartum depression in mothers, study finds

ScienceDaily (Oct. 19, 2010) — In contrast to the findings of some studies and the recommendations that pregnant women increase their intake of fish oil via dietary docosahexaenoic acid (DHA) because of the possible benefits, a randomized trial that included more than 2,000 women finds that use of DHA supplements did not result in lower levels of postpartum depression in mothers or improved cognitive and language development in their offspring during early childhood, according to a study in the October 20 issue of JAMA.

"Epidemiological investigations from the United States and Europe demonstrate that higher intakes of n-3 long-chain polyunsaturated fatty acids (LCPUFA) from fish and seafood during pregnancy are associated with a reduced risk of depressive symptoms in the postnatal period, as well as improved developmental outcomes in the offspring," the authors write. "However, n-3 LCPUFA intervention trials in human pregnancy have reported mixed results and have not been conclusive largely because of methodological limitations." The researchers add that trials focused on the developmental outcomes of children had high attrition rates and were not large in size.

"Despite the paucity of evidence, recommendations exist to increase intake of DHA in pregnancy, and the nutritional supplement industry successfully markets prenatal supplements with DHA to optimize brain function of mother and infant. Before DHA supplementation in pregnancy becomes widespread, it is important to know not only if there are benefits, but also of any risks for either the mother or child," the authors state.

Maria Makrides, B.Sc., B.N.D., Ph.D., of the Women's and Children's Health Research Institute, Adelaide, Australia and colleagues conducted a multicenter, randomized controlled trial to assess whether DHA supplementation during the last half of pregnancy reduced the risk of depressed maternal mood during the postpartum period and improved early cognitive development in offspring. The study, conducted in 5 Australian maternity hospitals, included 2,399 women with gestation of less than 21 weeks and who were recruited between October 2005 and January 2008. Follow-up of children (n = 726) was completed December 2009. Women received DHA-rich fish oil capsules (providing 800 mg/d of DHA) or matched vegetable oil capsules without DHA from study entry to birth. Of the 2,399 women enrolled, 96.7 percent completed the trial.

Levels of depression in mothers was measured with the Edinburgh Postnatal Depression Scale; cognitive and language development in children was assessed by the Bayley Scales of Infant and Toddler Development.

The researchers found that the percentage of women reporting high levels of depressive symptoms during the first 6 months postpartum did not differ between the DHA and control groups (9.67 percent vs. 11.19 percent). The percentage of women with a new medical diagnosis for depression during the trial or a diagnosis requiring treatment also did not differ between groups.

Also, average cognitive scores of children from women allocated to the DHA group did not differ from average scores of children of women from the control group; and overall, average language scores did not differ between groups. Other developmental outcomes, such as motor development and social-emotional behavior, did not differ between groups overall.

"Current recommendations suggest that pregnant women increase their dietary DHA to improve their health outcomes as well as those of their children. Such recommendations are increasingly being adopted with women taking prenatal supplements with DHA," the authors write. "However, the results of [this trial] do not support routine DHA supplementation for pregnant women to reduce depressive symptoms or to improve cognitive or language outcomes in early childhood."

"Our results are at odds with the results of some large-scale epidemiological studies. It may be that even well-conducted epidemiological studies overestimate effect size and do not adequately deal with residual confounding, or that other nutrients in fish and seafood, beyond DHA, contribute to the observations from epidemiological studies. Further studies are required to determine whether there are specific benefits of DHA supplementation for women with a previous history of depression and for women at risk of preterm birth."

Editorial: Fish, Fish Oil, and Pregnancy

Emily Oken, M.D., M.P.H., of Harvard Medical School and Harvard Pilgrim Health Care Institute, and Mandy B. Belfort, M.D., M.P.H., of Children's Hospital Boston, write in an accompanying editorial that additional research is needed regarding the potential benefits of DHA for mothers and children.

"Fish oil supplements are safe, well tolerated, and reduce risks for early preterm birth, which is associated with poor neurocognitive outcomes and maternal depression. Whether fish consumption during pregnancy will confer similar or perhaps even greater benefits for mothers and their children requires more investigation, including large randomized trials such as [this trial]. For now, pregnant women should take care to get the recommended intake of 200 mg/d of DHA, either by including low-mercury, high-DHA fish in their diets or by taking a daily n-3 PUFA supplement. The benefit of higher intakes remains unclear."

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by JAMA and Archives Journals.

Journal References:

Emily Oken, Mandy B. Belfort. Fish, Fish Oil, and Pregnancy. JAMA, 2010; 304 (15): 1717-1718 DOI: 10.1001/jama.2010.1541Maria Makrides; Robert A. Gibson; Andrew J. McPhee; Lisa Yelland; Julie Quinlivan; Philip Ryan; and the DOMInO Investigative Team. Effect of DHA Supplementation During Pregnancy on Maternal Depression and Neurodevelopment of Young Children: A Randomized Controlled Trial. JAMA, 2010; 304 (15): 1675-1683 DOI: 10.1001/jama.2010.1507

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Fish near coal-fired power plants have lower levels of mercury

ScienceDaily (Oct. 7, 2010) — A new study from North Carolina State University finds that fish located near coal-fired power plants have lower levels of mercury than fish that live much further away. The surprising finding appears to be linked to high levels of another chemical, selenium, found near such facilities, which unfortunately poses problems of its own.

"We found that fish in lakes located at least 30 kilometers (km) from a coal-fired power plant had mercury levels more than three times higher than fish of the same species in lakes that are within 10 km of a plant," says Dana Sackett, a Ph.D. student at NC State and the lead author of a paper describing the study. "This information will inform health and wildlife officials who make determinations about fish consumption advisories and wildlife management decisions."

The findings are surprising because coal-fired power plants are the leading source of mercury air emissions globally, and a significant amount of that mercury is expected to settle out of the air within 10 km of a plant's smokestacks. Mercury is a bioaccumulative toxin that builds up in animal tissues -- including fish -- and can pose public health problems related to fish consumption.

The researchers examined largemouth bass and bluegill from 14 freshwater lakes -- seven within 10 km of a plant and seven that were a minimum of 30 km from a plant. The species were chosen because they are commonly caught and eaten by recreational anglers, and because they represent two very different places in the food chain. Largemouth bass are apex predators at the top of the food chain, which consume smaller fish. As a result, since mercury builds up in the food chain, they would be expected to show higher levels of mercury. Bluegill are smaller fish that primarily dine on invertebrates, such as insects, and would be expected to show lower levels of mercury.

The researchers found that the mercury levels went up more than threefold in both species at lakes located further from the power plants, meaning that the location effect impacts fish regardless of their place in the food chain.

The researchers think that the lower mercury levels near power plants are likely linked to selenium levels. Fish tissue samples taken within 10 km of a coal-fired power plant showed selenium levels three times higher than samples taken from fish located further away. This shows an inverse relationship to the mercury levels -- the higher the selenium level, the lower the mercury level.

Selenium, which is also emitted by coal-fired plants, is known to have an antagonistic relationship to mercury, though the specific mechanisms at play are not clearly defined. In other words, the selenium prevents fish from accumulating high levels of mercury, and we're still working on the specifics of how that happens.

However, while lower mercury levels are a good thing, higher levels of selenium pose their own risks. "Selenium is an important dietary element," says Dr. Derek Aday, associate professor of biology at NC State and a co-author of the paper. "But at high levels, it can have serious consequences -- including lethal effects and an array of health problems for fish and wildlife."

The research was funded by the Water Resources Research Institute. The paper will be published in a forthcoming issue of the journal Ecotoxicology. The paper was co-authored by Sackett, Aday, Dr. James Rice, professor of biology at NC State, Dr. Gregory Cope, professor of toxicology at NC State, and Dr. David Buchwalter, assistant professor of toxicology at NC State.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by North Carolina State University.

Journal Reference:

Sackett, Dana et al. Does proximity to coal-fired power plants influence fish tissue mercury? Ecotoxicology, (in press)

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Consuming polyunsaturated fatty acids may lower the incidence of gum disease

ScienceDaily (Oct. 26, 2010) — Periodontitis, a common inflammatory disease in which gum tissue separates from teeth, leads to accumulation of bacteria and potential bone and tooth loss. Although traditional treatments concentrate on the bacterial infection, more recent strategies target the inflammatory response. In an article in the November issue of the Journal of the American Dietetic Association, researchers from Harvard Medical School and Harvard School of Public Health found that dietary intake of polyunsaturated fatty acids (PUFAs) like fish oil, known to have anti-inflammatory properties, shows promise for the effective treatment and prevention of periodontitis.

"We found that n-3 fatty acid intake, particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are inversely associated with periodontitis in the US population," commented Asghar Z. Naqvi, MPH, MNS, Department of Medicine, Beth Israel Deaconess Medical Center. "To date, the treatment of periodontitis has primarily involved mechanical cleaning and local antibiotic application. Thus, a dietary therapy, if effective, might be a less expensive and safer method for the prevention and treatment of periodontitis. Given the evidence indicating a role for n-3 fatty acids in other chronic inflammatory conditions, it is possible that treating periodontitis with n-3 fatty acids could have the added benefit of preventing other chronic diseases associated with inflammation, including stoke as well."

Using data from the National Health and Nutrition Examination Survey (NHANES), a nationally representative survey with a complex multistage, stratified probability sample, investigators found that dietary intake of the PUFAs DHA and (EPA) were associated with a decreased prevalence of periodontitis, although linolenic acid (LNA) did not show this association.

The study involved over 9,000 adults who participated in NHANES between 1999 and 2004 who had received dental examinations. Dietary DHA, EPA and LNA intake were estimated from 24-hour food recall interviews and data regarding supplementary use of PUFAs were captured as well. The NHANES study also collected extensive demographic, ethnic, educational and socioeconomic data, allowing the researchers to take other factors into consideration that might obscure the results.

The prevalence of periodontitis in the study sample was 8.2%. There was an approximately 20% reduction in periodontitis prevalence in those subjects who consumed the highest amount of dietary DHA. The reduction correlated with EPA was smaller, while the correlation to LNA was not statistically significant.

In an accompanying commentary, Elizabeth Krall Kaye, PhD, Professor, Boston University Henry M. Goldman School of Dental Medicine, notes that three interesting results emerged from this study. One was that significantly reduced odds of periodontal disease were observed at relatively modest intakes of DHA and EPA. Another result of note was the suggestion of a threshold dose; that is, there seemed to be no further reduction in odds or periodontal disease conferred by intakes at the highest levels. Third, the results were no different when dietary plus supplemental intakes were examined. These findings are encouraging in that they suggest it may be possible to attain clinically meaningful benefits for periodontal disease at modest levels of n-3 fatty acid intakes from foods.

Foods that contain significant amounts of polyunsaturated fats include fatty fish like salmon, peanut butter, margarine, and nuts.

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Elsevier Health Sciences, via EurekAlert!, a service of AAAS.

Journal References:

Asghar Z. Naqvi, Catherine Buettner, Russell S. Phillips, Roger B. Davis, Kenneth J. Mukamal. n-3 Fatty Acids and Periodontitis in US Adults. Journal of the American Dietetic Association, 2010; 110 (11)Elizabeth Krall Kaye. n-3 Fatty Acid Intake and Periodontal Disease. Journal of the American Dietetic Association, 2010; 110 (11)

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Got fish? Nutrition studies explore health benefits

ScienceDaily (Oct. 18, 2010) — Some of America's most popular fish--salmon and albacore tuna, for example--are rich in healthful natural compounds known as omega-3 fatty acids. Ongoing studies by U.S. Department of Agriculture (USDA) chemist Darshan S. Kelley and co-investigators are helping uncover new details about how these fish-oil components help protect us from chronic diseases.

Kelley is with the USDA Agricultural Research Service (ARS) Western Human Nutrition Research Center at the University of California-Davis. ARS is the USDA's principal intramural scientific research agency.

In an early study with laboratory mice, Kelley and colleagues investigated the interplay of two omega-3 fatty acids from fish oil-DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid)-and a third fatty acid, CLA (as trans-10, cis-12 CLA) found in some dietary supplements.

Kelley's 8-week test with 50 laboratory mice indicated that DHA protected the animals against two harmful side effects of CLA: CLA-induced insulin resistance and CLA-induced non-alcoholic fatty-liver disease. In contrast, EPA offered only partial protection against CLA-induced non-alcoholic fatty liver disease and provided no protection against insulin resistance.

If untreated, insulin resistance can lead to diabetes. An estimated 36 million to 57 million Americans are insulin-resistant. Non-alcoholic fatty liver disease can result in cirrhosis of the liver or liver cancer. The study appeared in a 2007 issue of Metabolic Syndrome and Related Disorders.

In related work, published in a 2009 article in Current Opinion in Clinical Nutrition and Metabolic Care, Kelley and University of California-Davis graduate student Dawn Fedor reviewed results from several dozen EPA and DHA studies. In their review, the scientists indicate that findings reported in the past decade have been inconsistent in regard to the effects of EPA and DHA on insulin resistance in human volunteers.

Their review underscores the need for new investigations, with larger numbers of volunteers. Kelley, for example, would like to determine whether DHA can improve the ability of adult, pre-diabetic volunteers to use insulin efficiently, and thus help delay onset of diabetes. Such research might reveal more about the mechanisms of action that DHA and EPA use, the sites upon which they act in the human body, and the genes that control these mechanisms.

Read more about the research in the October 2010 issue of Agricultural Research magazine, available online at: http://www.ars.usda.gov/is/AR/archive/oct10/nutrition1010.htm.

Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by USDA/Agricultural Research Service.

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New fish feeds made from fish byproducts

ScienceDaily (Oct. 6, 2010) — Fish byproducts may be a new source of fish feed, thanks to research by U.S. Department of Agriculture (USDA)-funded scientists in Hawaii.

Research scientist Dong-Fang Deng and her colleagues with the Oceanic Institute in Waimanalo, Hawaii, are collaborating with USDA food technologist Peter Bechtel to develop the new fish feeds. Bechtel is with the USDA Agricultural Research Service (ARS) Subarctic Agricultural Research Unit in Kodiak, Alaska. ARS is the USDA's principal intramural scientific research agency.

The scientists are taking fish parts that would normally be discarded-head, tail, bone, skin and internal organs-and fashioning them into feeds for shrimp and fish. They are currently testing the feeds on Pacific threadfin (Polydactylus sexfilis)-or "moi" as Hawaiians call it-and Pacific white shrimp (Litopenaeus vannamei).

The researchers then characterize the nutrient composition of the feeds, evaluate their ability to attract the shrimp and moi, estimate the food's digestibility and assess the growth of the animals. Recent tests have shown that many of the Alaska fish parts work well as feeding stimulants, which entice the shrimp to eat the plant-protein-based feed to which fish byproducts had been added.

In an earlier ARS-funded study with moi, former Oceanic Institute scientist Ian Forster found that the nutritional quality of feeds made with discarded portions of Alaskan pollock and cod was equivalent to that of feed made from Norwegian fishmeal, generally regarded as the highest standard in the aquaculture feed industry. Forster and his colleagues found the same result when feeds were tested on shrimp.

According to Deng, the scientists are currently examining how to best use fish byproducts to develop practical feeds that are nutritionally balanced, cost effective and safe for the environment.

Details about these feed studies have been published in the Journal of the World Aquaculture Society and the Journal of Aquatic Food Product Technology.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by USDA/Agricultural Research Service. The original article was written by Stephanie Yao.

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Female fish abandoned by males to raise offspring on their own

ScienceDaily (Sep. 21, 2010) — Caring for children can be a tough job, particularly if you are a female cichlid fish.

Native to the crater lakes of Nicaragua, cichlid fish look after their young by defending them against would-be predators. While male and female cichlid fish generally share parental responsibilities, research shows that this is not always the case.

Conducted by an international team of researchers that included two biologists from Monash University, and published in the journal Behavioral Ecology and Sociobiology, new research has shown that male cichlid fish have a propensity to desert their mates, leaving them to then look after the young as single parents.

In an attempt to understand the ecological factors underlying this behaviour, lead author, Dr Topi Lehtonen from the University of Turku in Finland, spent many hours underwater observing the parental behaviours of different cichlid fishes.

Dr Lehtonen and his colleagues, including Dr Bob Wong and Dr Andreas Svensson from Monash University and Professor Axel Myer from Konstanz University in Germany, found that mate desertion was more common among the larger cichlid species inhabiting the lakes and desertion was also more likely to take place later in the breeding season.

Dr Bob Wong, a Senior Lecturer in the Science Faculty at Monash University said the exact reasons why the male cichlid fish would abandon their mates and their offspring are not entirely clear, but the motivation is likely linked to the costs and benefits of extended care and the availability of additional mating opportunities.

"Regardless of motives, being deserted by their mate is bad news for the abandoned female cichlid fish and her young brood," Dr Wong said.

The research found that male desertion severely compromised the quality of care that females were able to provide to their young, particularly in defending their babies against formidable fish predators, such as the bigmouth sleeper fish.

"The findings provide important insights into animal mating systems, the evolution of parental care and the costs and benefits of caring for offspring," Dr Wong said.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Monash University.

Journal Reference:

Topi K. Lehtonen, Bob B. M. Wong, P. Andreas Svensson, Axel Meyer. Adjustment of brood care behaviour in the absence of a mate in two species of Nicaraguan crater lake cichlids. Behavioral Ecology and Sociobiology, 2010; DOI: 10.1007/s00265-010-1062-5

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Brainy worms: Scientists uncover counterpart of cerebral cortex in marine worms

ScienceDaily (Sep. 3, 2010) — Our cerebral cortex, or pallium, is a big part of what makes us human: art, literature and science would not exist had this most fascinating part of our brain not emerged in some less intelligent ancestor in prehistoric times. But when did this occur and what were these ancestors? Unexpectedly, scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have now discovered a true counterpart of the cerebral cortex in an invertebrate, a marine worm.

Their findings are published in Cell, and give an idea of what the most ancient higher brain centres looked like, and what our distant ancestors used them for.

It has long been clear that, in evolutionary terms, we share our pallium with other vertebrates, but beyond that was mystery. This is because even invertebrates that are clearly related to us -- such as the fish-like amphioxus -- appear to have no similar brain structures, nothing that points to a shared evolutionary past. But EMBL scientists have now found brain structures related to the vertebrate pallium in a very distant cousin -- the marine ragworm Platynereis dumerilii, a relative of the earthworm -- which last shared an ancestor with us around 600 million years ago.

"Two stunning conclusions emerge from this finding," explains Detlev Arendt, who headed the study: "First, the pallium is much older than anyone would have assumed, probably as old as higher animals themselves. Second, we learn that it came out of 'the blue' -- as an adaptation to early marine life in Precambrian oceans."

To uncover the evolutionary origins of our brain, EMBL scientist Raju Tomer, who designed and conducted the work, took an unprecedentedly deep look at the regions of Platynereis dumerilii's brain responsible for processing olfactory information -- the mushroom-bodies. He developed a new technique, called cellular profiling by image registration (PrImR), which is the first to enable scientists to investigate a large number of genes in a compact brain and determine which are turned on simultaneously. This technique enabled Tomer to determine each cell's molecular fingerprint, defining cell types according to the genes they express, rather than just based on their shape and location as was done before.

"Comparing the molecular fingerprints of the developing ragworms' mushroom-bodies to existing information on the vertebrate pallium," Arendt says, " it became clear that they are too similar to be of independent origin and must share a common evolutionary precursor."

This ancestral structure was likely a group of densely packed cells, which received and processed information about smell and directly controlled locomotion. It may have enabled our ancestors crawling over the sea floor to identify food sources, move towards them, and integrate previous experiences into some sort of learning.

"Most people thought that invertebrate mushroom-bodies and vertebrate pallium had arisen independently during the course of evolution, but we have proven this was most probably not the case," says Tomer. Arendt concludes: "The evolutionary history of our cerebral cortex has to be rewritten."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by European Molecular Biology Laboratory, via EurekAlert!, a service of AAAS.

Journal Reference:

Raju Tomer, Alexandru S. Denes, Kristin Tessmar-Raible, Detlev Arendt. Profiling by Image Registration Reveals Common Origin of Annelid Mushroom Bodies and Vertebrate Pallium. Cell, 2010; 142 (5): 800-809 DOI: 10.1016/j.cell.2010.07.043

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Why fish don't freeze in the Arctic Ocean: Chemists unmask natural antifreeze

ScienceDaily (Aug. 26, 2010) — Bochum researchers have discovered how natural antifreeze works to protect fish in the icy waters of the Arctic Ocean from freezing to death. They were able to observe that an antifreeze protein in the fish's blood affects the water molecules in its vicinity such that they cannot freeze, and everything remains fluid. Here, there is no chemical bond between protein and water -- the mere presence of the protein is sufficient.

Together with cooperation partners from the U.S., the researchers surrounding Prof. Dr. Martina Havenith (Physical Chemistry II of the RUB) describe their discovery in a Rapid Communication in the Journal of the American Chemical Society (JACS).

Better than household antifreeze

Temperatures of minus 1.8 °C should really be enough to freeze any fish: the freezing point of fish blood is about minus 0.9 °C. How Antarctic fish are able to keep moving at these temperatures has interested researchers for a long time. As long as 50 years ago, special frost protection proteins were found in the blood of these fish. These so-called anti-freeze proteins work better than any household antifreeze. How they work, however, was still unclear.

The Bochum researchers used a special technique, terahertz spectroscopy, to unravel the underlying mechanism. With the aid of terahertz radiation, the collective motion of water molecules and proteins can be recorded. Thus, the working group has already been able to show that water molecules, which usually perform a permanent dance in liquid water, and constantly enter new bonds, dance a more ordered dance in the presence of proteins -- "the disco dance becomes a minuet" says Prof. Havenith.

Souvenir from an Antarctic expedition

The subject of the current investigations was the anti-freeze glycoproteins of the Antarctic toothfish Dissostichus mawsoni, which one of the American partners, Arthur L. Devries, had fished himself on an Antarctic expedition.

"We could see that the protein has an especially long-range effect on the water molecules around it. We speak of an extended dynamical hydration shell," says co-author Konrad Meister.

"This effect, which prevents ice crystallization, is even more pronounced at low temperatures than at room temperature," adds Prof. Havenith.

Nevertheless, to freeze the water, lower temperatures would be necessary. Complexation of the AFP by borate strongly reduces the antifreeze activity. In this case, the researchers also found no change in the terahertz dance. The researchers' results provide evidence for a new model of how AFGPs prevent water from freezing: Antifreeze activity is not achieved by a single molecular binding between the protein and the water, but instead AFP perturbs the aqueous solvent over long distances. The investigation demonstrated for the first time a direct link between the function of a protein and its signature in the terahertz range.

The studies were funded by the Volkswagen Foundation.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Ruhr-University Bochum, via EurekAlert!, a service of AAAS.

Journal Reference:

Simon Ebbinghaus, Konrad Meister, Benjamin Born, Arthur L. DeVries, Martin Gruebele, Martina Havenith. Antifreeze Glycoprotein Activity Correlates with Long-Range Protein?Water Dynamics. Journal of the American Chemical Society, 2010; : 100816142208022 DOI: 10.1021/ja1051632

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Global fisheries research finds promise and peril: While industry contributes $240B annually, overfishing takes toll on people and revenue

ScienceDaily (Sep. 14, 2010) — Global fisheries, a vital source of food and revenue throughout the world, contribute between US$225-$240 billion per year to the worldwide economy, according to four new studies. Researchers also concluded that healthier fisheries could have prevented malnourishment in nearly 20 million people in poorer countries.

This first comprehensive, peer-reviewed estimate of the global economic contribution of fisheries was published online in four papers as part of a special issue of the Journal of Bioeconomics.

This research, conducted by the University of British Columbia's Fisheries Centre, with support from the Pew Environment Group, quantifies the social and economic value of fish around the world and also calculates the loss of both revenue and dependable protein sources from years of overfishing.

"We know fish play an important ecological role in the marine environment, but these studies assess their 'out-of-the-water' value to people across the globe," says lead economist Associate Professor Rashid Sumaila at the University of British Columbia's Fisheries Centre. "Whether you are looking at fish as a financial resource or a source of protein, our research shows that the benefits of healthy, robust fisheries have enormous value far beyond the fishing dock."

Dr. Sumaila and his team of researchers also found that:

Overfishing reduces revenue. Annually, estimated global catch losses from overfishing totaled up to seven to 36 per cent of the actual tonnage landed in a year, resulting in a landed value loss of between US$6.4-36 billion each year.Fishing has a multiplier effect. The fishing industry's economic impact on related businesses, such as boat building, international transport and bait suppliers, is roughly three times larger than the value of fish at first sale.Fisheries generate incomes. Wild fisheries generate more than US$63 billion in annual household incomes around the world.Non-industrial uses of the oceans are a net positive for economies and jobs. Recreational use of ocean ecosystems by sport divers, whale watchers and recreational fishermen contributes US$47 billion each year to national economies worldwide and generates nearly 1.1 million jobs.

One of the four papers focused on global fisheries subsidies, or financial incentives that countries offer to their fishing industries, which may contribute to depleted fish stocks. Large developed countries are spending twice the amount of tax-payer money on global fisheries subsidies that encourage overfishing than they are on subsidies that protect oceans.

"Many economies are paying doubly for continued overfishing of our oceans," says Sumaila. "First, tax-payer money is directly contributing to the decline of worldwide fisheries, and second, fishermen and undernourished people are hurting from a steadily declining resource. From a socioeconomic standpoint, subsidies that promote overfishing are doing far more harm than good."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of British Columbia.

Journal References:

U. Rashid Sumaila, Ragnar Arnason, Glenn-Marie Lange. Toward a global fisheries economics: an introduction to the special issue. Journal of Bioeconomics, 2010; DOI: 10.1007/s10818-010-9089-2U. Rashid Sumaila, Ahmed S. Khan, Andrew J. Dyck, Reg Watson, Gordon Munro, Peter Tydemers, Daniel Pauly. A bottom-up re-estimation of global fisheries subsidies. Journal of Bioeconomics, 2010; DOI: 10.1007/s10818-010-9091-8Andrés M. Cisneros-Montemayor, U. Rashid Sumaila. A global estimate of benefits from ecosystem-based marine recreation: potential impacts and implications for management. Journal of Bioeconomics, 2010; DOI: 10.1007/s10818-010-9092-7U. Thara Srinivasan, William W. L. Cheung, Reg Watson, U. Rashid Sumaila. Food security implications of global marine catch losses due to overfishing. Journal of Bioeconomics, 2010; DOI: 10.1007/s10818-010-9090-9Andrew J. Dyck, U. Rashid Sumaila. Economic impact of ocean fish populations in the global fishery. Journal of Bioeconomics, 2010; DOI: 10.1007/s10818-010-9088-3

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Why fish oils work swimmingly against inflammation and diabetes

ScienceDaily (Sep. 4, 2010) — Researchers at the University of California, San Diego School of Medicine have identified the molecular mechanism that makes omega-3 fatty acids so effective in reducing chronic inflammation and insulin resistance.

The discovery could lead to development of a simple dietary remedy for many of the more than 23 million Americans suffering from diabetes and other conditions.

Writing in the advance online edition of the September 3 issue of the journal Cell, Jerrold Olefsky, MD, and colleagues identified a key receptor on macrophages abundantly found in obese body fat. Obesity and diabetes are closely correlated. The scientists say omega-3 fatty acids activate this macrophage receptor, resulting in broad anti-inflammatory effects and improved systemic insulin sensitivity.

Macrophages are specialized white blood cells that engulf and digest cellular debris and pathogens. Part of this immune system response involves the macrophages secreting cytokines and other proteins that cause inflammation, a method for destroying cells and objects perceived to be harmful. Obese fat tissue contains lots of these macrophages producing lots of cytokines. The result can be chronic inflammation and rising insulin resistance in neighboring cells over-exposed to cytokines. Insulin resistance is the physical condition in which the natural hormone insulin becomes less effective at regulating blood sugar levels in the body, leading to myriad and often severe health problems, most notably type 2 diabetes mellitus.

Olefsky and colleagues looked at cellular receptors known to respond to fatty acids. They eventually narrowed their focus to a G-protein receptor called GPR120, one of a family of signaling molecules involved in numerous cellular functions. The GPR120 receptor is found only on pro-inflammatory macrophages in mature fat cells. When the receptor is turned off, the macrophage produces inflammatory effects. But exposed to omega-3 fatty acids, specifically docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the GPR120 receptor is activated and generates a strong anti-inflammatory effect.

"It's just an incredibly potent effect," said Olefsky, a professor of medicine and associate dean of scientific affairs for the UC San Diego School of Medicine. "The omega-3 fatty acids switch on the receptor, killing the inflammatory response."

The scientists conducted their research using cell cultures and mice, some of the latter genetically modified to lack the GPR120 receptor. All of the mice were fed a high-fat diet with or without omega-3 fatty acid supplementation. The supplementation treatment inhibited inflammation and enhanced insulin sensitivity in ordinary obese mice, but had no effect in GPR120 knockout mice. A chemical agonist of omega-3 fatty acids produced similar results.

"This is nature at work," said Olefsky. "The receptor evolved to respond to a natural product -- omega-3 fatty acids -- so that the inflammatory process can be controlled. Our work shows how fish oils safely do this, and suggests a possible way to treating the serious problems of inflammation in obesity and in conditions like diabetes, cancer and cardiovascular disease through simple dietary supplementation."

However, Olefsky said more research is required. For example, it remains unclear how much fish oil constitutes a safe, effective dose. High consumption of fish oil has been linked to increased risk of bleeding and stroke in some people.

Should fish oils prove impractical as a therapeutic agent, Olefsky said the identification of the GPR120 receptor means researchers can work toward developing an alternative drug that mimics the actions of DHA and EPA and provides the same anti-inflammatory effects.

Co-authors of the paper are Da Young Oh, Saswata Talukdar, Eun Ju Bae, Hidetaka Morinaga, WuQuiang Fan, Pingping Li and Wendell J. Lu, all in the Department of Medicine, Division of Endocrinology and Metabolism at the University of California, San Diego; Takeshi Imamura, Division of Pharmacology, Shiga University of Medical Science; and Steven M. Watkins, Lipomics Technologies, Inc.

Funding for this research came, in part, from a National Institutes of Health grant and the Eunice Kennedy Shriver NICHD/NIH.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of California - San Diego. The original article was written by Scott LaFee.

Journal Reference:

Da Young Oh, Saswata Talukdar, Eun Ju Bae, Takeshi Imamura, Hidetaka Morinaga, WuQiang Fan, Pingping Li, Wendell J. Lu, Steven M. Watkins, Jerrold M. Olefsky. GPR120 Is an Omega-3 Fatty Acid Receptor Mediating Potent Anti-inflammatory and Insulin-Sensitizing Effects. Cell, 2010; 142 (5): 687-698 DOI: 10.1016/j.cell.2010.07.041

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Creation of the first frozen repository for Hawaiian coral

ScienceDaily (Aug. 19, 2010) — Scientists at the Smithsonian Institution and the Hawaii Institute of Marine Biology at the University of Hawaii at Manoa have created the first frozen bank for Hawaiian corals in an attempt to protect them from extinction and to preserve their diversity in Hawaii.

Mary Hagedorn, an adjunct faculty member at HIMB and a research scientist with the Smithsonian Conservation Biology Institute, leads the laboratory at the HIMB research facilities on Coconut Island in Kaneohe Bay, Oahu, that is banking the frozen coral cells.

"Because frozen banked cells are viable, the frozen material can be thawed one, 50 or, in theory, even 1,000 years from now to restore a species or population," said Hagedorn. "In fact, some of the frozen sperm samples have already been thawed and used to fertilize coral eggs to produce developing coral larvae."

Coral reefs are living, dynamic ecosystems that provide invaluable services: They act as nursery grounds for marine fish and invertebrates, provide natural storm barriers for coastlines, purify carbon dioxide from the atmosphere and they are potential sources for undiscovered pharmaceuticals.

However, coral reefs are experiencing unprecedented levels of degradation due to human impact. Globally, greenhouse gasses from burning fossil fuels are warming the oceans, making them more acidic and causing corals to stress and bleach. As a result, the corals are more susceptible to emergent diseases. Locally, reefs are affected by pollution and sedimentation from poor land-use practices, nutrient run-off from farms and waste-treatment plants, and destructive practices such as dynamite fishing and trawls.

Unless action is taken now, coral reefs and many of the animals that depend on them may cease to exist within the next 40 years, causing the first global extinction of a worldwide ecosystem during current history.

"This work highlights the importance of basic science and discovery for developing creative solutions to pressing conservation problems," said Steve Monfort, director of the Smithsonian Conservation Biology Institute. "We are confident that this effort will one day help to restore these vital marine ecosystems."

Saving reef habitat alone will not stop corals' decline because many of the most serious threats are global rather than local. Done properly over time, researchers can store samples of frozen material and place them back into ecosystems to infuse new genes and vigor into natural populations, thereby enhancing the health and viability of wild stocks.

Currently, the Hawaiian bank contains frozen sperm and embryonic cells from mushroom coral (Fungia scutaria) and rice coral (Montipora capitata), but it is only a beginning. The researchers hope to store many of the corals that are important to Hawaiian reefs.

Helping with this project are two student summer interns supported by the Smithsonian Women's Committee: Malia Paresa (a senior at the University of Southern California) and Kelly Martorana (a recent graduate of California Polytechnic State University in San Luis Obispo). This internship was an incredible experience for both women, but especially relevant to Paresa, who grew up five minutes from Kaneohe Bay.

"Before this internship, I had no idea how dire the situation was that many coral species are facing, and now I am much more aware that all of their hardships are caused by anthropogenic activities," said Paresa. "As a native Hawaiian and Kaneohe native, I take great pride in making a difference in the future of Hawaiian coral reefs. If we act quickly enough, we can make a difference to their future." In addition, visiting scientist, Dr. Kamal Sarma from the Central Agricultural Research Institute on Nicobar and Andaman Islands, and Virginia Carter and Ann Farrell from the Smithsonian are assisting.

This research is funded by the Smithsonian, HIMB, Morris Animal Foundation and Anela Kolohe Foundation.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Hawaii at Manoa.

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Snail mail beats phones to help feds sustain ample fish stocks in US coastal waters

ScienceDaily (Sep. 1, 2010) — Old-fashioned snail mail with a postage stamp might be the answer for federal officials struggling to keep the waters off the U.S. coast from being overfished.

Anglers who fish for fun in U.S. coastal waters say the federal government currently relies on questionable data to determine which ocean locales are overfished and subsequently placed off limits to recreational and commercial fishing so stocks can rebuild.

The government through the National Marine Fisheries Service has relied heavily on a home telephone survey since the 1970s to random-digit dial coastal households for information about fishing trips.

Now a pilot study in North Carolina has found a new way to calculate recreational fishing activity in the ocean -- and it's proven promising as a method to replace calling people on the phone, according to statistician Lynne Stokes, one of five researchers who conducted the North Carolina pilot study.

The study is part of a national overhaul of the way the Fisheries Service collects and reports on recreational fishing data known as the Marine Recreational Information Program, or MRIP. The Fisheries Service is part of the National Oceanic and Atmospheric Administration, the lead federal agency mandated with protecting and conserving marine life and habitat off the nation's coasts.

In fact, the study found that the new questionnaire mailed to selected households via the U.S. Postal Service netted a higher response rate and more complete data, said Stokes, a professor in the Department of Statistical Science at Southern Methodist University in Dallas.

Snail mail is the new telephone

The mail survey asked recreational anglers for the same information as the phone survey -- how often they had recently gone fishing off the coast."It's kind of like back to the future," said Stokes. "This study showed that the mail survey data collection for this particular survey is quite promising. The data was better and we got a higher response."

Stokes was a member of a National Research Council panel that was asked by the government to critique its existing "Coastal Household Telephone Survey."

The Coastal Household Telephone Survey is carried out regularly by the National Marine Fisheries Service to routinely assess fish stocks in U.S. coastal waters.

Survey critical to fisheries management

Fisheries scientists rely heavily on survey data to determine which areas off the coast are overfished for specific types of fish.

The service manages overfishing in various ways, including by imposing annual limits on the amount and type of fish that can be caught and by declaring moratoriums on fishing.

A new law requires the NOAA Fisheries Service to step up protection and conservation. But anglers say it's unfair to use unreliable data to set limits and moratoriums on fishing -- which causes hardship for the nation's massive recreational fishing industry.

There are 13 million recreational saltwater anglers in the nation, according to the Congressional Sportsmen's Foundation. Recreational fishing has an $82 billion annual impact on the nation's economy and supports 533,000 jobs, according to the American Sportfishing Association.

The nation's coastal waters are divided into eight Regional Fishery Management Councils created in 1976 to manage the fishery resources within the federal 200-mile limit off the coast. The councils are: New England, Mid-Atlantic, South Atlantic, Gulf of Mexico, Caribbean, Pacific, North Pacific and Western Pacific. The closing this year of the red snapper fishery in the South Atlantic council area has sparked intense controversy.

NOAA has said that U.S. fisheries contribute more than $35 billion annually to the economy, with an estimated $20 billion spent on recreational fishing alone each year.

Mail survey shows promise

Results of the study were presented as "A Pilot Test of a Dual Frame Mail Survey of Recreational Marine Anglers" in August at the 2010 annual meeting of the American Statistical Association in Vancouver.

Other researchers included Nancy Mathiowetz, University of Wisconsin-Milwaukee; J. Michael Brick, Westat; William R. Andrews, NOAA Marine Recreational Information Program; and Seth Muzzy, ICF/Macro.

The researchers chose North Carolina because the state has had a saltwater recreational fishing registry for some time. The purpose of the research is to improve both survey coverage and response rates.

"Phone responses are declining at an alarming rate," Stokes said, partly due to the jump in households that only have cell phones. "People are just less cooperative with phone surveys."

The survey was mailed to 1,800 anglers and included a $1 cash incentive, with a reminder postcard one week later. The rate of response was higher to the mailed surveys than to phone surveys, Stokes said, which is consistent with a general U.S. phone survey trend since the 1980s.

The experiment also showed that a large fraction of North Carolina anglers do not live in coastal county households, which are the only ones directly covered by the current phone survey. Efforts to improve coverage by adding interviews with anglers from registry lists are easier by mail than phone since duplicates are easier to identify, she said.

Solution for shortcoming

A shortcoming of the mailed survey is the inability to get real-time information, which allows the NOAA Fisheries Service to respond quickly to overfishing. Stokes said that problem may be able to be resolved by providing a revised forecast, similar to routinely released economic data for unemployment, job claims, manufacturing and consumer confidence.

Evidence was found that the mail survey suffers from what Stokes described as "avidity bias": People who fish a lot and who are licensed to fish are more likely to respond. The researchers will address that in a revised survey by asking people for information about other recreational activities as well.

Eventually the NOAA Fisheries Service survey will tap anglers on the National Saltwater Angler Registry. A new federal law requires anyone planning to recreational fish in the ocean be signed up with the registry, which the NOAA Fisheries Service launched in January.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Southern Methodist University.

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Shallow water habitats important for young salmon and trout

ScienceDaily (Aug. 31, 2010) — Research carried out at the University of Gothenburg shows that competition from older fish causes young salmon and trout to seek refuge in shallow water. Preserving such habitats may, therefore, be important for the survival of the young fish.

Using field studies in watercourses north of Gothenburg and laboratory experiments in Denmark and Scotland, scientist Rasmus Kaspersson at the Department of Zoology, University of Gothenburg, has studied the competition between different age groups of Atlantic salmon and brown trout.

Forced into shallow water

It has previously been believed that poor swimming ability forces young salmon and trout to remain in shallow habitats where the water flows at a lower velocity. Rasmus Kaspersson's work, however, shows that it is rather competition for habitats from the older fish that compels young fish to use shallow water. Rasmus Kaspersson's experiments show that young-of-the-year move to deeper parts of the watercourse as soon as the number of older individuals is reduced.

"This suggests that young-of-the-year actually prefer to live in deep, rapidly flowing water, where they can find food easier and are protected from predatory birds and mink," says Rasmus Kaspersson.

Population determines survival

In the natural world, however, older and younger individuals are both present, and shallow habitats then function as refuge for the younger fish. The weight and length of young-of-the-year increased when older individuals were removed from parts of the watercourses studied. Thus it seems that the population of older salmon and trout in a watercourse affects indirectly the number of young-of-the-year that reach adulthood.

More protected habitats required

The results presented in Rasmus Kaspersson's thesis show how important it is to preserve and restore shallow parts of Swedish watercourses with low-velocity flow. This will provide more protected habitats for the young fish.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Gothenburg, via AlphaGalileo.

Journal Reference:

R. Kaspersson, J. H?jesj?. Density-dependent growth rate in an age-structured population: a field study on stream-dwelling brown trout Salmo trutta. Journal of Fish Biology, 2009; 74 (10): 2196 DOI: 10.1111/j.1095-8649.2009.02227.x

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View the original article here

Ending the oceans' 'tragedy of the commons'

ScienceDaily (Sep. 15, 2010) — Leading international marine scientists are proposing radical changes in the governance of the world's oceans to rescue them from overfishing, pollution and other human impacts.

Based on a successful experiment in Chile, the researchers say a new approach to marine tenure could help to reverse the maritime 'tragedy of the commons' which has led to the depletion of fish stocks worldwide.

"Marine ecosystems are in decline around the world. New transformational changes in governance are urgently required to cope with overfishing, pollution, global changes, and other drivers of degradation," says Professor Terry Hughes of the ARC Centre of Excellence for Coral Reef Studies and James Cook University, one of the authors of a new scientific paper advocating sweeping reform of ocean governance.

"In recent years there has been a growing appreciation that the health of ecosystems like the oceans and human wellbeing are closely linked," says co-author Dr. Per Olsson of the Stockholm Resilience Centre. "Unfortunately, typical governance arrangements don't effectively link these two essential elements, when trying to manage fishing pressure for example. They are often too rigid and don't cope well with surprises or changed conditions."

A combination of fisheries collapses and the move to democracy in Chile, quite by chance, provided the opportunity to try out some new arrangements for looking after fisheries, involving a partnership of fishers, scientists and managers.

"There was a general recognition that Chile's fish stocks were in trouble," says Professor Carl Folke, also from the Stockholm Resilience Centre and the Beijer Institute. "Things were turbulent and people were looking for answers and that made them open to new approaches. There was also good scientific understanding of the coastal ecosystems of the region on which to base a new management plan."

Fishers and scientists had been working together on the problem for some years, sharing knowledge and building trust. This led to the trialling of new co-operative models for fishery management, based on the latest that science can reveal about the state of the fish stock and the surrounding marine ecosystem.

The result is a revolutionary national system of marine tenure that allocates user rights and responsibilities to collectives of fishers.

"Although fine tuning is always needed to continue to build resilience of this new regime, this transformation has improved the sustainability of the interconnected social-ecological system," Prof Folke adds.

A vital ingredient in the change was the move by Chile to democracy after a 17-year dictatorship. This opened the way for reform of the laws governing fishing rights.

The new laws gave exclusive ocean territories to local 'artisanal' fishers, and excluded the big industrial fishing fleets, which had their own exclusive fishing zone.

Scientists and small fishers then worked together to understand and rebuild the shattered fish stocks in their zone, leading to a shared vision and voluntary agreements on how to manage them. Fishing pressure was reduced in the industrial fishing zone by cutting the number of big vessels.

Professor Hughes says the Chilean experience contains lessons which can potentially apply anywhere in the world where a fishery is in trouble and there is good scientific data on the marine environment.

"You need a shared recognition that something has to be done, you need a good understanding of the marine ecosystem and how to regenerate it, you need a strong rapport between scientists and fishers, and you need a political moment when sweeping changes can be brought in," he says.

"If you have all those things, there is a good chance you can avoid the marine 'tragedy of the commons' which has been a feature of fisheries around the world in the past half century."

The research indicates the key to managing fisheries may depend on creating agreements that are both voluntary and flexible enough to cope with changes in the ocean environment, leading to fisheries that are both ecologically and socially sustainable.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by ARC Centre of Excellence in Coral Reef Studies.

Journal Reference:

Gelcich et al. Navigating transformations in governance of Chilean marine coastal resources. Proceedings of the National Academy of Sciences, 2010; DOI: 10.1073/pnas.1012021107

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Taking the pulse of coral reefs

ScienceDaily (Sep. 25, 2010) — Healthy reefs with more corals and fish generate predictably greater levels of noise, according to researchers working in Panama. This has important implications for understanding the behaviour of young fish, and provides an exciting new approach for monitoring environmental health by listening to reefs.

Contrary to Jacques Cousteau's 'Silent World', coral reefs are surprisingly noisy places, with fish and invertebrates producing clicks and grunts which combine to produce cacophonies of noise. Each reef is subtly different depending on the size and composition of the resident community.

By analysing recordings of coral reefs from the Las Perlas Archipelago in Pacific Panama (Central America), marine biologists have found that some reefs are noisier than others, and these differences in noise provide useful information about the state of the reef. Exeter University PhD student Emma Kennedy and her supervisor Dr Steve Simpson, working with an acoustician Dr Marc Holderied, also from the University of Bristol's School of Biological Sciences, found that healthier reefs were louder, with a clear association between overall noise level generated and the amount of living coral.

A more detailed investigation of the sound produced by some of the reefs showed that lower frequency sounds provided more information on the numbers of fish living on the reef, while the intensity of higher frequency reef sounds gave an indication of coral diversity. This is the first time that a link has been made between noise generated by individual reefs and the specific habitats and communities making up that reef.

Previous work by Dr Steve Simpson has shown that larval fish and corals returning to reefs after spending their first few weeks out in the plankton, search for habitat by listening out for, and moving towards, reef noise. Sound travels well underwater, meaning that noise produced by a reef can propagate several kilometres out to sea.

Dr Simpson said: "This study provides evidence that reef generated sound contains a real richness of information. This would provide fish and invertebrates with the cues they need to assess the quality of potential settlement sites before they can see them, a bit like wandering around a music festival eavesdropping on different bands before choosing where to pitch your tent. It may even provide the information that enables some fish to return to the very reef on which they were originally spawned."

The study also highlights the potential for using audio recordings to monitor the health of reefs. Usually, scientific assessment of reef health requires teams of scuba divers and huge quantities of equipment and so is costly, time consuming and difficult in remote areas. In this study, scientists dropped a cable off the side of the boat with a hydrophone (underwater recording device) attached. A two-minute recording contained enough information to distinguish between reefs. This is a very encouraging find for the development of acoustic recordings as ecological survey or monitoring tools.

The team are hoping that their findings will prompt other scientists to investigate reef sound further.

Emma Kennedy said: "Investigation of the acoustic properties of reefs is a relatively new area of science but already we're realising that there's more to underwater noises than just whale and dolphin communication! Reefs may be broadcasting a lot of information out into the sea that both humans and marine animals could use. We're hoping that our findings will encourage more research into this area, and are excited this might lead to the development of new tools for assessing reef health."

The research was a collaborative effort carried out from the Smithsonian Tropical Research Centre with Dr Hector Guzman (STRI) and Professor Hamish Mair at Heriot-Watt University in Edinburgh.

The research is published in the Journal of Experimental Marine Biology and Ecology, and was funded by Natural Environment Research Council (NERC, UK) grants to Steve Simpson and Emma Kennedy.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Bristol.

Journal Reference:

E.V. Kennedy, M.W. Holderied, J.M. Mair, H.M. Guzman, S.D. Simpson. Spatial patterns in reef-generated noise relate to habitats and communities: Evidence from a Panamanian case study. Journal of Experimental Marine Biology and Ecology, 2010; DOI: 10.1016/j.jembe.2010.08.017

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Massive coral mortality following bleaching in Indonesia

ScienceDaily (Aug. 17, 2010) — The Wildlife Conservation Society has released initial field observations that indicate that a dramatic rise in the surface temperature in Indonesian waters has resulted in a large-scale bleaching event that has devastated coral populations.

WCS's Indonesia Program "Rapid Response Unit" of marine biologists was dispatched to investigate coral bleaching reported in May in Aceh -- a province of Indonesia located on the northern tip of the island of Sumatra. The initial survey carried out by the team revealed that over 60 percent of corals were bleached.

"Bleaching" -- a whitening of corals that occurs when algae living within coral tissues are expelled -- is an indication of stress caused by environmental triggers such as sea surface temperature fluctuations. Depending on many factors, bleached coral may recover over time or die.

Subsequent monitoring conducted by marine ecologists from WCS, James Cook University (Australia), and Syiah Kuala University (Indonesia) were completed in early August and revealed one of the most rapid and severe coral mortality events ever recorded. The scientists found that 80 percent of some species have died since the initial assessment and more colonies are expected to die within the next few months.

The event is the result of a rise in sea surface temperatures in the Andaman Sea -- an area that includes the coasts of Myanmar, Thailand, the Andaman and Nicobar Island, and northwestern Indonesia. According to the National Oceanic and Atmospheric Administration's Coral Hotspots website, temperatures in the region peaked in late May of 2010, when the temperature reached 34 degrees Celsius -- 4 degrees Celsius higher than long term averages for the area.

"It's a disappointing development particularly in light of the fact that these same corals proved resilient to other disruptions to this ecosystem, including the Indian Ocean Tsunami of 2004," said WCS Indonesia Marine Program Director Dr. Stuart Campbell.

WCS and JCU have been working in the region since March 2005. Surveys conducted in the wake of the Indian Ocean Tsunami in 2004 revealed that the many reefs of Aceh were largely unaffected by this massive disturbance. Indeed, reefs severely damaged by poor land use and destructive fishing prior to the tsunami had recovered dramatically in the intervening years due to improved management. Government and community-managed areas in the region have been remarkably successful at maintaining fish biomass despite ongoing access to the reefs. But the bleaching and mortality in 2010 have rapidly reversed this recovery and will have a profound effect on reef fisheries.

Of particular concern is the scale of the sea surface temperature anomaly which the NOAA website indicates has affected the entire Andaman Sea and beyond. Similar mass bleaching events in 2010 have now been recorded in Sri Lanka, Thailand, Malaysia and many parts of Indonesia.

"If a similar degree of mortality is apparent at other sites in the Andaman Sea this will be the worst bleaching event ever recorded in the region," according to Dr. Andrew Baird of the ARC Centre of Excellence for Coral Reef Studies at JCU. "The destruction of these upstream reefs means recovery is likely to take much longer than before."

"This is a tragedy not only for some of the world's most biodiverse coral reefs, but also for people in the region, many of whom are extremely impoverished and depend on these reefs for their food and livelihoods," said WCS Marine Program Director Dr. Caleb McClennen. "Immediate and intensive management will be required to try and help these reefs, their fisheries and the entire ecosystem recover and adapt. However, coral reefs cannot be protected from the warming ocean temperatures brought on by a changing climate by local actions alone. This is another unfortunate reminder that international efforts to curb the causes and effects of climate change must be made if these sensitive ecosystems and the vulnerable human communities around the world that depend on them are to adapt and endure."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Wildlife Conservation Society, via EurekAlert!, a service of AAAS.

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Clues to gut immunity evolution: Research reveals similarities between fish and humans

ScienceDaily (Aug. 12, 2010) — A study at the University of Pennsylvania School of Veterinary Medicine has identified the function of one of the earliest antibodies in the animal kingdom, an ancient immunoglobulin that helps explain the evolution of human intestinal immune responses. It was discovered to play a predominant role in the guts of fish and paves the way for a better understanding of human gut immunity as well as for safer, healthier approaches to keeping fish from pathogen infections.

The findings appear in the online version of Nature Immunology and will be featured on the cover of the September issue.

The study identified unique aspects of the structure and function of a fish antibody, IgT, and points to this molecule as the most ancient vertebrate immunoglobulin specialized in mucosal immunity. The findings challenge the present paradigm that specialization of immunoglobulin isotypes into different body areas, i.e., intestine and blood, arose during the evolution of four-legged creatures, or tetrapods. While IgT was discovered five years ago, its structure and function remained an enigma.

In addition to characterizing the protein structure of IgT, the study provides direct evidence for the existence of a novel B cell lineage uniquely producing IgT. In the gut, IgT+ B cells represent the predominant B cell subset. More critically, the study showed that responses of rainbow trout IgT to an intestinal parasite were only detected in the gut, whereas IgM responses were confined to plasma. Supporting further the role of IgT in mucosal immunity, the researchers found that a majority of trout intestinal bacteria were coated with IgT. The research team concluded that the specialization of immunoglobulin isotypes into different body compartments is a universal feature of all jawed vertebrate immune systems, a feature required for health maintenance in environmentally different exposed body areas that require different immune needs.

"Immunoglobulins like IgA, IgX and the newly discovered IgT are evolutionarily distant," said Oriol Sunyer, associate professor in the Department of Pathobiology at Penn Vet. "Their specialization into mucosal compartments must have occurred independently by a process of convergent evolution driven by similar selective pressures operating on the gut environment of fish, amphibians and mammals."

Significantly, the study shows that fish IgT and human IgA systems appear to utilize similar solutions to maintain healthy intestines, therefore Sunyer indicated that "future studies on IgT will further unravel structural and functional aspects of human mucosal immunoglobulins that are key to their role in keeping our intestines free of pathogens."

With aquaculture being the fastest growing animal food sector in the United States, as well as in the global marketplace, the findings should also impact fish health and vaccinology. In that regard, all prior studies carried out in teleost fish during the last few decades have missed the specific contribution of IgT in protecting fish from pathogens. Sunyer's studies establish that teleost fish contain not one, as originally believed, but at least two functional immunoglobulins, IgM and IgT, that respond to pathogenic challenge in different body areas. Thus, the new capability of measuring not only IgM but also IgT responses will greatly facilitate the evaluation and understanding of fish immune responses as well as the protective effects of fish vaccines.

"The design of future fish vaccines is likely to be more effective, stimulating not only systemic but also mucosal immunity as we are now able to measure IgT-induced responses," Sunyer said.

"Dr. Sunyer's work will change how we look at disease prevention in fish, and his breakthrough will have a profound impact on the future of the aquaculture industry," said Roger Beachy, director of the National Institute of Food and Agriculture. "I am proud that the USDA supports such innovative research."

Immunoglobulins first emerged in vertebrates around 400 million years ago along with the appearance of the jawed fish, the most ancient living vertebrate species with jaws. Throughout evolutionary time, immunoglobulins diversified into several isotypes with specialized roles in innate and adaptive immunity in different parts of the body, according to the study's author, who says the study of immunoglobulins from fish and other animal species will continue providing new insights that are fundamental for understanding the role of these molecules in protecting us against pathogens.

The research was funded by the National Science Foundation, the National Institutes of Health and the United States Department of Agriculture.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Pennsylvania.

Journal Reference:

Yong-An Zhang, Irene Salinas, Jun Li, David Parra, Sarah Bjork, Zhen Xu, Scott E LaPatra, Jerri Bartholomew, J Oriol Sunyer. IgT, a primitive immunoglobulin class specialized in mucosal immunity. Nature Immunology, 2010; DOI: 10.1038/ni.1913

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Magnetic attraction for fish, crabs? Study examines whether magnetic fields from aquatic power sources affect animals

ScienceDaily (Sep. 20, 2010) — Super-sized electromagnetic coils are helping explain how aquatic life might be affected by renewable energy devices being considered for placement along America's coastal waters and in the nation's rivers.

Scientists with the Department of Energy's Pacific Northwest National Laboratory are examining whether a variety of fish and invertebrates change their behavior during and after exposure to an electromagnetic field similar to those produced by marine and hydrokinetic power devices that capture energy from ocean waves, tides, currents and rivers. Research began this summer and will continue for two years.

PNNL marine ecologist Jeff Ward is discussing this research at Oceans 2010, an ocean engineering conference being held in Seattle. The conference is being hosted by the Marine Technology Society and the Institute of Electrical and Electronic Engineers' Oceanic Engineering Society.

"The ocean's natural ebb and flow can be an abundant, constant energy source," said PNNL oceanographer Andrea Copping, who is the principal investigator on the project out of PNNL's Marine Sciences Laboratory in Sequim, Wash. "But before we can place power devices in the water, we need to know how they might impact the marine environment."

Energy companies and utilities are looking at using several different technologies to harness energy from oceans and rivers. Marine power could come from devices that move with rolling waves on the ocean's surface or from underwater turbines that spin with the tides and currents. And hydrokinetic devices would be similar to marine power devices, but generate power from free-flowing water in rivers and streams. Whatever the design, each device generates electricity that travels through cables that connect the device with a land power line. Researchers want to know how the devices and their cables affect marine life.

Electrical magnetism

This research project is using two specially designed coils at PNNL's Marine Sciences Laboratory. The coils, called Helmholtz coils, each consist of about 200 pounds of copper wiring wrapped into a window frame-like outline that's roughly five feet by five feet. The wiring carries electricity at the flip of a switch. Like any electricity, this creates an electromagnetic field that naturally attracts magnetic materials like iron. The field around the electrical coil can create between 0.1 and 3 milliTeslas of magnetic flux. Three milliTeslas is about three-tenths the magnetic flux of a typical small bar magnet. Previous research into how electromagnetic fields affect marine animals has been in the 3 to 5 milliTesla range.

Researchers want to know if the electromagnetic field will also affect marine and estuarine animal behavior, including migration, finding food and avoiding predators. Several aquatic animals -- such as sharks, skates, salmon, sea turtles and lobsters -- may use the Earth's natural magnetic fields like a compass to navigate and detect their prey.

To test the field's potential effects, aquarium tanks filled with marine species are being placed near the two coils. Then researchers will activate the electromagnetic field -- at various strengths and time periods -- to see if the animals' actions change.

For example, researchers will observe whether the electromagnetic field interferes with the ability of juvenile Coho salmon to recognize and avoid predators. Young salmon normally stop swimming, go low and stay still when they detect a predator. Also, the scientists will examine whether the typically fast, flicking movements of Dungeness crab antennules -- the small antennae next to crabs' eyes that help them detect odors -- change when exposed to the electromagnetic field. And researchers will document whether the animals are attracted or repelled by the fields.

"We really don't know if the animals will be affected or not," Ward said. "There's surprisingly little comprehensive research to say for sure."

New frontiers

There have been some limited studies in this area, but most have been conducted outside the United States and involved animals that aren't common in U.S. waters. Ward noted this project will help develop a broader body of information from which scientists, marine power developers and the regulatory agencies that permit the power devices can draw to determine how proposed devices could affect certain marine life at a given site.

If animals demonstrate a noticeable behavior change in the controlled environment of laboratory tests, PNNL researchers may conduct a field study with test animals placed near pilot marine power devices such as the one Snohomish County PUD has proposed for Admiralty Inlet in Washington state's Puget Sound.

As part of the project, scientists at Oak Ridge National Laboratory are also examining how electromagnetic fields created by hydrokinetic devices, which generate power from free-flowing water in rivers and streams, might affect freshwater animals. And researchers from Northwest National Marine Renewable Energy Center at Oregon State University are also studying the potential electromagnetic effects on crabs.

This study is a component of PNNL's larger research effort to better understand the potential environmental impact of marine and hydrokinetic energy development. PNNL researchers are also examining whether underwater noise from these devices could impact aquatic life, whether underwater animals could be injured by the rotating turbines in tidal power devices and how marine devices could impact the flow patterns of coastal waters. All this work is being funded by DOE's Office of Energy Efficiency & Renewable Energy, Wind and Water Power Program.

Ward will discuss this research during a marine renewable energy session at Oceans 2010. For more information about Oceans 2010, go to http://www.oceans10mtsieeeseattle.org/.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by DOE/Pacific Northwest National Laboratory, via EurekAlert!, a service of AAAS.

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Marine scientists unveil mysteries of life on undersea mountains

ScienceDaily (Sep. 21, 2010) — They challenge the mountain ranges of the Alps, the Andes and the Himalayas in size yet surprisingly little is known about seamounts, the vast mountains hidden under the world's oceans. Now in a special issue of Marine Ecology scientists uncover the mystery of life on these submerged mountain ranges and reveal why these under studied ecosystems are under threat.

The bathymetry of our oceans is now resolved at a scale and detail unimaginable by early pioneers and recent estimates suggest that, globally, there may be up to 100,000 seamounts, yet less than 300 have been well studied. Recognising this scarcity of knowledge provided the motivation for CenSeam, a seamount-focused field research project within the Census of Marine Life which commenced in 2005.

"The field of seamount ecology is rife with ecological paradigms, many of which have already become cemented in the scientific literature and in the minds of advocates for seamount protection," said Dr Ashley Rowden, one of the principal investigators of CenSeam. "Together, these paradigms have created a widely held view of seamounts as unique environments, hotspots of biodiversity with fragile ecosystems of exceptional ecological worth."

The special issue puts major paradigms in seamount ecology under the microscope to assess their status against the weight of existing evidence to date, and against the backdrop of the latest findings.

Researchers challenged the theory that seamounts act as hotspots of species richness, the weight of evidence now suggests that seamounts may have comparable levels of diversity and endemism to continental margins. However, it appears that their ecological communities are distinct in structure, and are of higher biomass than neighbouring continental margins.

The geographical differences between seamount communities have suggested limited larval dispersal, local speciation, geographic isolation, or a combination of all these processes. New genetic research presented in the special issue addresses these themes, documenting complex patterns of connectivity among species populations that depend on spatial scale, physical barriers, and life history characteristics.

Much seamount research has been born out of the need to better manage these potentially vulnerable ecosystems. Globally, seamount ecosystems are under pressure from bottom-contact fishing and other human-related impacts. Researchers detail the footprint of trawling and a risk assessment confirms what has long been suspected: seamount communities are highly vulnerable to disturbance by bottom trawling and recovery from fishing impacts is a lengthy process, likely requiring decades at a minimum.

It is also predicted that shallowing of the aragonite saturation horizon caused by ocean acidification is expected to place deepwater corals at risk, but researchers pose that the summits and upper flanks of seamounts may yet provide a spatial refuge from these impacts.

"It is hoped" says Thomas Schlacher, lead editor of the volume "that the papers in this special issue will challenge some of the previously held concepts about seamount ecosystems, and hopefully stimulate and help guide future research endeavours both on seamounts, and across the wider deep-sea realm."

Research papers from the Census of Marine life have been published in two special issues of the Marine Ecology, published by Wiley-Blackwell. The Census of Marine Life's latest title Life in the World's Oceans: Diversity, Distribution and Abundance, also published by Wiley-Blackwell, which includes the research of CenSeam, will be available in October.

About the Census of Marine Life

The Census of Marine Life is a global network of researchers in more than 80 nations engaged in a 10-year scientific initiative to assess and explain the diversity, distribution, and abundance of life in the oceans. The Census of Marine Life is an unprecedented undertaking that is significantly contributing to understanding of the marine environment and life in the global ocean. Census researchers are discovering new life forms, finding life in unexpected places, advancing technology to create windows into what was an opaque ocean, and building global partnerships to advance what is known about life below the surface. For more information about the Census of Marine Life visit: http://www.coml.org

About the Journal

Marine Ecology is published on behalf of Stazione Zoologica di Napoli and publishes original contributions on the structure and dynamics of marine benthic and pelagic ecosystems, and on the critical links between ecology and evolution of marine organisms. Visit the journal on Wiley-Online Library here: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1439-0485

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Wiley - Blackwell, via AlphaGalileo.

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Seafood stewardship questionable, experts argue

ScienceDaily (Sep. 1, 2010) — The world's most established fisheries certifier is failing on its promises as rapidly as it gains prominence, according to leading fisheries experts from the University of British Columbia (UBC), Scripps Institution of Oceanography at the University of California at San Diego and elsewhere.

Established in 1997 by the World Wildlife Fund and Unilever, one of the world's largest fish retailers, the Marine Stewardship Council (MSC) has been helping consumers eat fish "guilt-free" by certifying fisheries. Major North American grocery chains such as Wal-Mart, Whole Foods and Europe's Waitrose carry seafood bearing the blue-mark label as part of their sustainability strategy.

But in an opinion piece published in the current issue of Nature, six researchers from Canada, Italy and the U.S. object to the many of the MSC's procedures and certification of certain species.

"The MSC is supposed to be a solution, but a lot of what they do has turned against biology in favour of bureaucracy," says Jennifer Jacquet, lead author and post-doctoral fellow with UBC's Sea Around Us Project.

The largest MSC-certified fishery, with an annual catch of one million tonnes, is the U.S. trawl fishery for pollock in the eastern Bering Sea. It was certified in 2005 and recommended for recertification this summer.

"Pollock has been certified despite a 64 per cent decline of the population's spawning biomass between 2004 and 2009, with no solid evidence for recovery. This has worrisome implications for possible harmful impacts on other species and fisheries besides the viability of the pollock fishery itself," says Jeremy Jackson from Scripps Institution of Oceanography at UC San Diego. "How is that sustainable?"

Paul Dayton, also of Scripps Oceanography, and David Ainley, a biologist who works in the Antarctic, remain concerned about the recent certification of krill and the proposed certification of toothfish.

"The certification of the Ross Sea is an embarrassment as it flies in the face of existing data and denies any sense of precautionary management," says Dayton.

"We're especially concerned about the recent certification of Antarctic krill despite estimates of long-term decline and a link between krill population depletion and declining sea ice in areas sensitive to climate change," says Daniel Pauly, head of UBC's Sea Around Us Project. "The rationale for this certification is on further thin ice because the catch is destined to feed farmed fish, pigs and chicken."

Fisheries that are being heavily depleted, reliant on high-impact methods such as bottom trawling and that aren't destined for human consumption should be excluded from certification, conclude the authors, which include Sidney Holt, a founding father of fisheries science.

"The MSC should not certify fisheries that are not demonstrably sustainable, fisheries that use high-impact methods such as bottom trawling and/or fisheries that aren't destined for human consumption," says Pauly.

"The MSC needs to strengthen its commitment to its own principles in order to fulfill its promise to be 'the best environmental choice,'" says Jackson.

The authors also note that the current certification system, which relies on for-profit consultants and could cost as much as $150,000, presents a potential conflict of interest and discriminates against small-scale fisheries and fisheries from developing countries -- most of which use highly-selective and sustainable techniques.

Dayton points out that "the failure of the MSC hurts the populations that are not sustainably taken and their ecosystems; it deprives the public of an opportunity to make a meaningful choice and it damages those fisheries that are well managed -- this is especially important for those sustainable small-scale fisheries competing with the giants that buy certifications they have not earned."

"Unless MSC goes under major reform, there are better, more effective ways to spend the certifier's $13-million annual budget to help the oceans, such as lobbying for the elimination of harmful fisheries subsidies or establishing marine protected areas," says Jacquet.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of British Columbia.

Journal Reference:

Jennifer Jacquet, Daniel Pauly, David Ainley, Sidney Holt, Paul Dayton, Jeremy Jackson. Seafood stewardship in crisis. Nature, 2010; 467 (7311): 28 DOI: 10.1038/467028a

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A tale of two atolls

ScienceDaily (Aug. 22, 2010) — Coral reefs -- kaleidoscopes of pink anemones and silver sharks -- are the planet's most colorful ecosystems and among its most endangered, say marine scientists.

As global warming raises ocean temperatures, many corals blanch and die, a phenomenon called "coral bleaching." And pumping large amounts of carbon dioxide into the atmosphere could make the ocean more acidic, further decimating corals and the fish that depend on them for food and shelter.

Millions of people inhabit coral reefs around the world, putting additional pressure on reef menageries. Establishing sustainable fisheries, even at remote islands and atolls, could significantly slow the decline of many reefs, say marine ecologists.

"We know that fishing can dramatically change the composition of a reef ecosystem," said Fiorenza Micheli, a professor of biology at Stanford University's Hopkins Marine Station. "By confronting overfishing immediately, we may increase the resilience of coral reefs to global warming and other threats."

To gain new insights on the ecology of reef fishing, Micheli and a team of Stanford researchers are taking advantage of an ongoing "natural experiment" at two isolated Pacific atolls -- Palmyra and Tabuaeran (or Fanning Island) -- located about 1,000 miles south of Hawaii. The project is funded by Stanford's Woods Institute for the Environment.

Separated by just 250 miles of ocean, the two atolls are worlds apart in terms of fishing pressure. Palmyra, a protected U.S. wildlife refuge, is virtually uninhabited and bars fishing along its shores. But Tabuaeran, part of the island nation of Kiribati (pron. "kee-ree-bahs"), is home to about 2,500 people who depend on the reef for food and income.

With support from a Woods Institute Environmental Venture Projects grant, a team of marine ecologists, oceanographers and anthropologists has been working alongside residents of Tabuaeran to better understand their fishing techniques and priorities. At the same time, the researchers are conducting underwater surveys to assess the populations and diversity of marine life at both atolls.

"By contrasting near-pristine Palmyra with inhabited and fished Tabuaeran, we are in a unique position to gather data that will ultimately help reef managers protect these vibrant and vulnerable habitats," Micheli said.

A tale of two atolls

Fieldwork at Palmyra and Tabuaeran began in 2007. On one trip, researchers -including several Stanford undergraduates -- donned snorkeling gear and counted the number and variety of fish species along sample areas at various reefs. Preliminary results from the underwater census suggest that the two atolls host very different communities of animals, in part because of the impact of fishing.

"Palmyra has some of the highest densities of sharks and other large fish of any coral reef in the world," said Douglas McCauley, a graduate student working with Micheli. "That's clear within seconds of jumping in the water there."

But at Tabuaeran, where fishing is a way of life, sharks and other large species are in short supply, McCauley said. "That was surprising, because Tabuaeran is a somewhat lightly populated island," he explained. "Most people arrived only a few decades ago, and fishing there is still very artisanal in nature."

Big fish grow and reproduce slowly, so their populations take longer to recover, he added. "It appears that it takes very little harvesting to reduce populations of these sensitive, large reef fish," McCauley said.

Trophy catches like sharks and the 100-pound bumphead parrotfish were the first to decline, he said. Highly prized by Tabuaerans, parrotfish have bottomless appetites that can alter the architecture of their coral homes. "The parrotfish's large size allows it to break off and crunch up whole branches of coral," McCauley said. "It plays a unique and important role in reef ecology that's simply not achieved by other fish species."

By spending hours in the water making detailed observations of bumphead parrotfish eating habits, the team is trying to piece together what a reef without these heavy eaters would look like.

Shark ecology

Sharks are also important for healthy coral reef ecosystems. For decades, conservationists have tried to protect reef sharks by setting aside reserves like Palmyra that provide a safe space to grow and reproduce. But sharks tagged at Palmyra have been caught by fishermen at reefs hundreds of miles away, McCauley said.

Shark tissue also contains unique ratios of carbon and nitrogen isotopes that identify its reef of origin. By sampling shark tissue, Stanford marine scientist Rob Dunbar confirmed that these top predators have been straying far from their home reefs.

"At Palmyra, we're finding that some sharks don't stay at home like we thought, so managers can't protect them outside the sanctuary borders," McCauley said. "It seems that effective management strategies for gray reef sharks and other similarly wide-ranging species will need to be thought out at much larger scales."

Shark meat is an important part of local diets, and shark fins garner large sums of money from traders who re-sell them to soup manufacturers. In 2009, Stanford anthropologists Bill Durham and Doug Bird, along with graduate student Eleanor Power, monitored the activities of Tabuaeran fishermen on daily forays for reef animals and conducted interviews with atoll elders on the history of local fishing. The results of these surveys will be used to assess fishing patterns and provide information to Tabuaeran leaders looking to achieve sustainable harvests.

Sustainable future

Because the livelihoods of so many Tabuaerans depend on healthy fisheries, locals are eager to preserve fish numbers, McCauley said. "Those who depend most on the environment can and should be its best stewards," he added.

To engage the next generation of Tabuaerans, researchers taught science classes at local schools three times a week on topics such as reef ecology and genetics. The Stanford team also conducted town hall meetings at every village on the atoll.

To broaden the scope of the project, team members have shared their results with Kiribati government officials, who face the twin challenges of geography and poverty. With a population of about 100,000, the Republic of Kiribati is one of the least developed countries on Earth, consisting of more than 30 atolls spread across about 1.3 million square miles of open ocean. In 2006, the government established one of the world's largest and most isolated marine reserves -- the Phoenix Islands Protected Area, a chain of virtually untouched atolls west of Tabuaeran.

"The government has been an ally in our work," Micheli said. "We hope our efforts will assist them in ensuring the long-term sustainability of their reef fisheries and will be a source of information and inspiration for other tropical Pacific communities as well."

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Stanford University. The original article was written by Daniel Strain.

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